Test tube experiments suggest that humans paid a high cost for developing immunity to this bug: it may have left us much more susceptible to another retrovirus, HIV.

初步试验发现，我们对这种病毒的免疫力是以极大的代价换来的：为了抵抗它，人类对艾滋病病毒的抵抗力被大幅削弱。

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One, who is dyslexic, had paid to have audio recordings made of his study materials and had spent several hours a day revising for the test.

其中一位有阅读困难的消防员花钱请人将他的学习资料录音并且每天花数小时复习备考。

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Health providers would be paid for "doing the right thing" rather than being paid for every test and procedure, he said.

CNN: Tax credits at heart of McCain's health care proposal

John O'Dowd said he was concerned the test was being paid for by an anonymous donor.

BBC: John O'Dowd calls for exam donor to be named

The authority said it had paid a local IT company to test the security of its internal systems in May 2012.

BBC: Hackers target Kent Council Council's computer systems